Asian Lillies disease or insect?

Asked May 10, 2018, 11:32 PM EDT

Several of our asian lilies are showing brown shriveled leaves. Is this likely insect damage or a disease? What is the recommended treatment? Should we cut down the affected stalks?

Benton County Oregon

3 Responses

Thank you for sending the images.

Because the symptoms don’t match the common diseases or disorders of lilies, I consulted with a plant disease specialist. He wondered, as did I, if frost could have damaged the leaves some weeks ago. Another thought is perhaps they remained wet too long after a rain event or from overhead watering.

How do you water the lilies? I see what appears to be a drip line in the background of one of the images. If that’s the system you use, where are the drippers placed and how long, also how often, is the system run?

The disease specialist suggested that you might “Leave them alone and keep an eye on them. If it is environmental or some similar abiotic thing then they might get better as time goes on.” Another suggestion is to consider removing the flower buds “to strengthen bulb or at least not tax them anymore.”

If the plants change for the worse, please update with new images and a history of what occurred in the interim.

Hi Jean, thanks for the response. We too questioned the disease diagnosis because it didn't look like any of the photos we saw on line.

The whole garden is on an automated drip system. The irrigation had not yet been turned on for the season when I posted my query.

We did turn on it this weekend. It is on for about three minutes three times a day.

We dug up a bulb with a couple of stalks and took it in to a local garden center. The fellow there took one look and declared "Botrytis." The pictures and descriptions on line mentioned white spots associated with Botrytis and they were absent. He suggested a sulfur spray and I have done so. I replanted the bulb we dug up.

The most necrotic stalks have been cut down. I'll let you know how the season progresses.


My thought was also that it might be botrytis. That's why I mentioned "perhaps they remained wet too long after a rain event or from overhead watering." However, the plant disease specialist didn't think the damage looked quite right for botrytis.

Botrytis often develops a thick gray fuzz but, can be atypical and the affected tissue simply turns brown. Even so, sulfur is only effective before the damage occurs.

In any event, Let's hope that all will now be well.